Patent Document 1 (International Publication No. WO2010/109962) discloses a polyetherimide fiber having excellent heat resistance and a small single fiber fineness suitable for producing fabrics.
Patent Document 2 (International Publication No. WO2007/111809) discloses a method for obtaining a colored polyetherimide fiber, the method including extruding a polyetherimide polymer to obtain a spun fiber and cheese-dyeing the spun fiber to give a dyed fiber.